Safety and Reliability of Embedded Systems - Software Engineering ...

Calculation Method 1: Minimal Cut Sets The top-event is the union of all intersection-free minimal cut sets If cut-set probabilities are small (below 0.1), then intersectionprobabilities are even smaller The top-event probability is the sum of all MCS probabilities∑P top= P MCSall MCS The probability of each MCS is the product of the probabilities of theincluded basic events∏P MCS= P iall events ∈MCSi This algorithm leads to an approximation. It does not work for NOT gatesSafety and Reliability of Embedded Systems© Prof. Dr. Liggesmeyer, 10Finding Minimal Cut Sets Decompose the tree recursively For each OR gate• Generate as many entries as there are inputs {(i1), (i2), (i3)...} For each AND gate• Generate one entry containing all inputs {(i1, i2, i3,...)} Repeat until all gates are resolved Cancel cut sets that are not minimal (redundant)Safety and Reliability of Embedded Systems© Prof. Dr. Liggesmeyer, 116